1. Field of the Invention
The present invention relates to a wireless terminal and a wireless system that wirelessly transmit or receive a video.
2. Description of the Related Art
All patents, patent applications, patent publications, scientific articles, and the like, which will hereinafter be cited or identified in the present application, will hereby be incorporated by reference in their entirety in order to describe more fully the state of the art to which the present invention pertains.
Conventionally, according to a method in which a video receiving terminal selects a video from a plurality of video transmitting terminals and displays a selected video, a video signal switching apparatus (a switcher) is arranged between the video receiving terminal and the transmitting terminals, each terminal is connected to the video signal switching apparatus using cables, and video selection is performed by controlling the video signal switching apparatus. When the number of video receiving terminals and video transmitting terminals to be used is increased, there is a problem that wiring by cables and the configuration of the video signal switching apparatus are complicated and it is not possible to quickly cope with a change in the layout of the video receiving terminals and the video transmitting terminals.
In recent years, with the improvement of wireless transmission technology, since it is possible to wirelessly transmit a high vision video from a video transmitting terminal to a video receiving terminal, a method in which a video to be displayed on the video receiving terminal is selected by switching a wireless connection between the video receiving terminal and the video transmitting terminal has been considered.
As a method for setting a combination of connections among a plurality of wireless terminals, Japanese Patent (Granted) Publication No. 3441422 discloses a wireless system including the plurality of wireless terminals that exchange data, and a wireless control terminal that instructs the combination of the connections. The present wireless system includes means that discovers wireless terminals within a range reachable by radio from the wireless control terminal, and a user interface for selecting wireless terminals to be connected from the discovered wireless terminals, and a method in which a connection instruction is transmitted to each of the selected wireless terminals through the user interface so that a wireless connection from a plurality of wireless terminals to an arbitrary wireless terminal is established has been disclosed.
FIG. 13 and FIG. 14 illustrate a connection switching operation of a wireless terminal. In FIG. 13, video transmission is performed between a video transmitting terminal 10a and a video receiving terminal 20a and between a video transmitting terminal 10b and a video receiving terminal 20b. At this time, when a connection switching instruction is wirelessly transmitted from a control terminal 30 to the video transmitting terminals and the video receiving terminals, it is possible to switch a wireless connection such that video transmission is performed between the video transmitting terminal 10a and the video receiving terminal 20b and between a video transmitting terminal 10c and the video receiving terminal 20a, as illustrated in FIG. 14.
However, in the wireless system, as illustrated in FIG. 15, there are cases in which the control terminal is unable to discover a video transmitting terminal and a video receiving terminal within a connectable range according to an arrangement position of a video transmitting terminal/a video receiving terminal and the control terminal and a wireless environment. In detail, since a video receiving terminal 20a can be connected to a video transmitting terminal 10a, a video transmitting terminal 10b, and a video transmitting terminal 10c, but a control terminal 30 is not able to discover the video transmitting terminal 10c, there are situations in which the control terminal 30 is not able to instruct a wireless connection between the video receiving terminal 20a and the video transmitting terminal 10c. 